Match the following and choose the correct combination from the option given
`{:(,,"I","","II"),(,a,"Nitrogen base",1,"RNA"),(,b,"Nucleoside",2,"Thymidylic acid"),(,c,"Nucleotide",3,"Cytidine"),(,d,"Nucleic acid",4,"Uracil"):}`

Options

A. a - 1, b - 2, c - 3, d - 4
B. a - 1, b - 3, c - 2, d - 4
C. a - 4, b - 3, c - 2, d - 1
D. a - 4, b - 1, c - 2, d - 3

Answer

To solve the matching question, we will analyze each item in Column 1 and find its corresponding match in Column 2.

### Step-by-Step Solution:

1. **Identify Nitrogen Base**:
- Nitrogen bases are components of nucleotides and nucleosides, and they include purines and pyrimidines.
- In the options provided, the only nitrogen base listed is **Uracil**.
- **Match**: Nitrogen base (I) → Uracil (4)

2. **Identify Nucleoside**:
- A nucleoside consists of a nitrogenous base attached to a sugar molecule.
- The only option that fits this description is **Cytidine**, which is formed from the nitrogenous base Cytosine and a ribose sugar.
- **Match**: Nucleoside (II) → Cytidine (3)

3. **Identify Nucleotide**:
- A nucleotide is made up of a nitrogenous base, a sugar, and a phosphate group.
- **Thymidylic acid** is a nucleotide formed from the nitrogenous base Thymine, ribose sugar, and phosphate.
- **Match**: Nucleotide (III) → Thymidylic acid (2)

4. **Identify Nucleic Acid**:
- Nucleic acids include DNA and RNA, which are polymers of nucleotides.
- The only option that corresponds to a nucleic acid is **RNA**.
- **Match**: Nucleic acid (IV) → RNA (1)

### Final Matches:
- A (Nitrogen base) → 4 (Uracil)
- B (Nucleoside) → 3 (Cytidine)
- C (Nucleotide) → 2 (Thymidylic acid)
- D (Nucleic acid) → 1 (RNA)

### Correct Combination:
The correct combination is **C**:
- A → 4
- B → 3
- C → 2
- D → 1